Packed gas-liquid contact towers for the contacting of a gas and a liquid are used in various treating and chemical operations, such as to include, but not be limited to: distillation, absorption, scrubbing, stripping and other operations and usually contain a liquid distribution means to distribute a downwardly flowing liquid generally uniformly over the upper surface of packing in the column. The packing may be random, that is, dumped, packing or structured packing or a combination thereof. Gas-liquid contact towers are employed for example for the contacting of and in processes using corrosive fluids, such as gases and liquids as in absorption towers used in the manufacture of sulfuric acid. A gas-liquid absorption contact tower is used to absorb sulfur trioxide from an ascending gas stream containing sulfur trioxide by counter current contact with a descending liquid stream of a relatively dilute sulfuric acid which acts as an absorption liquid stream. The dilute sulfuric acid absorbing liquid is introduced into the upper portion of the column and into a distributor, generally a main tubular or trough distributor having a plurality of extending arms with vertical distributor tubes with the ends of the vertical tubes extending to and buried within random packing generally smaller in size than the random packing used in the column proper for the gas-liquid contact. The employment of the smaller random packing about the ends of the vertical liquid distribution tubes is done to minimize splashing of the corrosive liquid and the formation of sprays and mists and to eliminate any mist formed, that is, sulfuric acid entrained droplets in the sulfur trioxide gas leaving the surface of the packed bed.
In such operations due to the highly corrosive nature of the gas and liquid, the packing is a random packing of ceramic-type material, that is, for example, ceramic rings or saddles which may range in size for example of about three inches for the main portion of the packing in column, while the random packing employed to bury the tube ends is typically about 11/2 to 2 inches in size. The tubular liquid distributor is usually constructed of heavy cast iron to provide corrosion allowance or exotic-type metal to resist corrosion from the corrosive liquid spray or mist. The tubular distributor which contains a plurality of generally vertical liquid distribution tubes, for example, one to four per square foot of the column cross section, are designed to deliver the sulfuric acid scrubbing liquid directly on to the top surface of the random ceramic packing so as to avoid splashing and sulfuric acid misting.
It is desirable, particularly in gas-liquid contact of corrosive fluids, such as in the manufacture of sulfuric acid, hydrogen chloride and other corrosive liquid materials, to provide a new and improved method and structure to reduce spray and mist and also to permit the use of a distributor that is corrosive-resistant at a reasonable cost to avoid the use of expensive, heavy or exotic metal liquid distributors. Therefore, it is desirable to provide for an improved gas-liquid column with improved spray and mist elimination and a method of reducing spray and mist generation with corrosive fluids in a gas-liquid contact column.